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<DIV>Dear Gmx'ers:</DIV>
<DIV> </DIV>
<DIV>As mentioned in the publication about shell water model, a shell particle
is connected to a dummy atom by a spring-like connection with the following
relationship:</DIV>
<DIV> </DIV>
<DIV>1. K=sqr(qS)/(4*PHI*Epsilon*alpha), </DIV>
<DIV>2. rsd=(4*PHI*Epsilon*alpha)*E / qS; (rsd is the distance between
shell and dummy particles at any moment, and E is refered to electrical field
strength).</DIV>
<DIV> </DIV>
<DIV>Anyone can tell me where is the definition of two equations above,
especially in the case of<STRONG> "isotropic
polarization",</STRONG> in GMX source code.</DIV>
<DIV>Because in my simulation, what I want to polarized is not a water molecule.
So I need a definite instruction, any suggestion?</DIV>
<DIV> </DIV>
<DIV>Secondly, how can I read the calculated value of spring constant
K by GMX after I defined "alpha" and "qS"? Can "debug" realize it? If yes, how?
Although I have used GMX for a long time, but that is the first time for me to
encounter such a problem.</DIV>
<DIV> </DIV>
<DIV>Waiting for your response, any instruction will be greatly
appreciated.</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>Xie Yinghong</DIV>
<DIV>Hong Kong Univ.</DIV></BODY></HTML>